Foxing is a term describing the age-related spots and browning seen on vintage paper documents such as books, postage stamps, certificates, and so forth. The name is believed to derive from the fox-like reddish-brown color of the stains. Paper so affected is said to be "foxed."
While unsightly, and a negative factor in the value of the paper item for collectors, foxing does not affect the integrity of the paper.
It is believed that high humidity contributes to foxing.
Using laser-based techniques to remove foxing stains from old paper is a potential solution to the problem. The use of lasers however, at longer wavelengths, is usually accompanied by side effects, since the affected area requires higher laser energies to be cleaned.
Depending on how valuable one's print or map is, one could try lightly dabbing 3% hydrogen peroxide onto the affected area using a cotton swab or cotton bud. This process is effective but one should test the paper in a less critical area first. It doesn't take much and one should not soak the spots; the hydrogen peroxide will bleach the ink just as it will bleach the foxing. Patience and repeated applications are best.
US Patent Issued to Deckers Outdoor on Jan. 25 for "Recycled Bicycle Tire Foxing Tape for Footwear and Method of Making Footwear" (California, Oregon Inventors)
Jan 28, 2011; ALEXANDRIA, Va., Jan. 28 -- United States Patent no. 7,874,084, issued on Jan. 25, was assigned to Deckers Outdoor Corp. (Goleta,...
Publication No. WO/2009/123231 Published on Oct. 8, Assigned to KING JIM for Binding-Fastener Fixing Device, Molding Die, Foxing Object Device (Japanese Inventors)
Oct 12, 2009; GENEVA, Oct. 12 -- Tatsuya Haneda and Hiroshi Shimada, both of Japan, have developed a binding-fastener fixing device, molding...